On November 1, 2010 the U.S. Army Corps of Engineers (Corps) approved a preliminary jurisdictional determination (JD) of potential waters of the United States (waters) for the Rosemont Copper Company (Rosemont) alignment of the Santa Rita Road utility line alternative (SPL-2008-00816-MB), under Corps Regulatory Guidance Letter (RGL) 08-02 for Preliminary JDs. Subsequently, approximately 38 acres of additional Rosemont Holdings (Addendum Area) were added to the alignment, near a “pinch point” (a narrow connection of Rosemont Holdings between other privately owned lands) around the old Helvetia Townsite, located in portions of Sections 22 and 23, Township 18 South, Range 15 East, Gila and Salt River Base Meridian (Figures 1 and 2). WestLand Resources, Inc. (WestLand) has completed a delineation of potential waters within the Addendum Area, as documented in this report.
WestLand Resources Inc. 2012a. Addendum to the Preliminary Jurisdictional Determination For Rosemont's Santa Rita Road Utility Line: 38 Acres Near the Helvetia Townsite, Pima County, Arizona. Project No. 1049.32 806 806. Prepared for U.S. Army Corps of Engineers. Tucson, AZ: WestLand Resources, Inc. March 13.